Phonograph record



April 26, 1932.

E. 1. QUINBY A 1,855,69

PHONOGRAPH RECORD FiledY oct. 21, 1930 12 /efca/eo/Ns T pf was INVENTOR E. JAY GUINBY BY www ATTORN EY illustrates clearly Patented Apr. 26, 1932 UNITED STATES PATENT OFFICE EDWN JAY QUINBY, 0F YONKERS, NEW YORK, ASSIGNOR T0 RADIO CORPORATION OF AMERICA, A CORPORATION OF DELAWARE .PHONOGRAPH RECORD Original application iled September 14, 1927, Serial No. 219,522, and in Canada. June 15, 1928. Divided and this application filed October 21, 1930, Serial No. 490,205.

This application is a division of my copending application- Serial Number 219,522 filed September 14th 1927, which has matured into Patent'1,785,0l7 granted December 16th 1930.

This invention relates to Ithe art of phonograph record making and deals more specifically with a phonograph or other type of recording having a sound track recorded thereon by the method and means for preventing mistracking disclosed in the aforementioned application. Mistracking as applied to afphonograph record refers to the shifting of the needle from 4one groove to another, which obtains when the wall between two successive grooves in the record breaks down. For example, the Victor Red Seal record No. 6648-13, upon which is recorded the composition Pomp and Circumstances, a large size $2.00 record made-by the Chicago Symphony Orchestra with the grand organ, when examined under a magnifying glass the possibilities of the phenomenon of mistracking after the record has been played a Ifew times. particular record at those portions where there is recorded the lower register pipes of the grand organ augmented by the beating of the tympani, the super position of the high amplitude low frequencies of these instruments causes a wide displacement in the groove of the record. It so happens that at several portions of the. record two adjacent grooves are formed with peaks which are positioned so that their crests are almost in contact with each other. This 'is shown, for example, in Fig. 1 of the drawing. Obviously, the thin wall which exists between the crests of these two peaks will soon break down, when the record is in use, and the needle. of the reproducing device may thus'be shifted radially from one groove to the other to produce mistracking.

Referring particularly to Fig. 1, if the needle jumps from A to C during the playing of therecord this constitutes a skip and a portion of the record will be omitted; whereas if the needle, when it has reached the position C in groove 2, jumps back to the point E in groove 1, this constitutes a repeat with the ,ord is being played.

consequent disagreeable effects when the rec- 'This tendency to mist-rack has been reduced in the past by the introduction of filters designed to eliminate, to various extents, some of the lower frequencies as, for instance, cor- ,respond to the'lower register pipes of the orurne controls reduced the high amplitudes re-- sulting from extra loud passages, so that the e'orts of the artists to color up their work with various volume shading and contrast were defeated, and in the recordation the result tended towards a monotonous constant volume. In short, records made in accordance with these methods were lacking in the original volume expression, and the lower frequencies employed by the artists who performed for them were either totally or partially absent. y

It/i's, therefore, an object of this invention to overcome the objection of mistracking in phonograph records without distorting the quality and fidelity of the sound recorded.

Further, it is an object of this invention to provide a phonograph record having grooves so spaced that the walls will not break down during normal use of the record over an extended period of time, and to accomplish this improvement without reducing the present playing-time standards and without increasing the present diameter standards of the records.

Further, it is an object of this invention to provide a record with grooves in which a substantially uniform well thickness is provided between such grooves.

It is a further object of this invention to provide a' method of cutting phonograph records, in which the lateral speed of the cutting tool is varied in such a way as to provide. substantially uniform thickness of the walls between the grooves, regardless of the character of program reproduced thereon. Further, it is an object of this invention to provide a method. and means for recording concert material in its natural state as produced by the artists without resorting to filtering or changing the relative volume values employedjby the performing artists, or other alteration to properly make the record.

It is a further vobject of this invention generally to improve the art of phonograph record cutting.

These and other objects of the invention will be readily apparent to those skilled in 16 the art from the following description taken in connection with the accompanying drawings in which:

' Fig. 1 is a partial diagrammatic showing of a record which is subject to the phenomezo non of mistracking; and

Fig. 2 is a diagrammatic representation of a system embodying the invention. 4

Referring in detail to Fig. 2 a disc 11 upon which the record is to be made is rotatably 25 mounted at 12. A cutting device 13, which may be of any of the types well known in the art, is carried by the shaft 14 which is rotatably coupled tothe drive motor 15. The members 13 and 14 are in threaded relation a0 so that rotation ofthe member 14 moves the trolled by an operator who varies the speed l of the drive mtor 15 as desired. Thus, when the program consists of very high 'amplitude frequency notes or of extremely high volume material, the operator increases the speed of thecmotor 15'thus causing the cutter 13 to travel radially of the disc 11 at a greater rate of speed, with a consequent result that' the walls between the two successive grooves are of a greater thickness. Of course, as soon las the program material is 4changed in character the operator merely reduces the speed of the drive motor 415 accordingly. To operate this`control mechanism, it is advisable that the operator be familiar with the composition recorded and also that he be able to read musical: scores. It has been found most desirable in controlling the .go changes of the speed of operation of the motor 15,to anticipate the occurrence of high amplitude low frequencies, or to anticipate any great increase 1n am litude of low freuencies, by one revolution of the record. he degrees of lead, however, between the the character of the sound. recorded.

The scope of this invention, therefore, is not to be limited b the present disclosure ex- 'cept as outline in the appended claims.

What I claim is: 1. A phonograph disc record having an undulated groove extending spirally between points near the circumference and center of said disc, said undulations varying in amplitude, and a lwall formed between adjacent portions of said groove, said wall havi 1 A mg a predetermined minimum thickness throu hout its len h. V

2. phonograp disc record having an undulated groove extending spirall between' 90; points. near the center and 'circum erence of said disc, the undulations in' said groove varying in accordance with the amplitude of materlal recorded on said disc, a. continuous wall formed between adjacent portions of said oove and extendin `spiral y therewith, the t 'ckness of-said wal \being greater adjacent to the portions of said groove in which the undulations corres onding to higher amplitudes are recorde and less at portions of said wall adjacent to the portions of saidl groove where undulations of less amplitude are recorded.

3. A record for the re roduction of sound having a sound trackf ereon, the position 105 of which varies according to the character of the sound recorded. 1

4. A record for the reproduction of sound comprisin a member having a plurality of sound trac portions therein which vary 1n distance from `each other according to the character of the sound recorded. A

. 5. A record forthe reproduction of sound, comprisin a member havinga sound recordedt ereon, and a second sound track on said member at a distance from said first track which varies according to the character of the sound recorded.

6. A record for the reproduction of sound comprising a member having a sound' track recorded thereon, portions of said sound track being adjacent to other portions of said ,sound track, and aispace between saidA adjacent portions which varies according to 7. A record for the reproduction of sound com rising abody having a sound track recpr ed thereon in a manner such .that portions of said soundtrack are adjacent to other portionsV of said sound track, the por- 13o kis small.

tions of said sound track in which the amplitude of vibrationis relatively large being spaced from adjacent portions by greater dlstances than portions of said track in which the amplitude of vibration is relatively small. f

8. A record for the reproduction ofsound having a soundtrack recordedthereon, ortions of which have been shifted substantially laterally in accordance with the character of the sound recorded.

9. A record for the reproduction of sound having a sound track recorded thereon, portions of said track in which the amplitude of vibration is large being spaced farther away from an adjacent recordin than portions of the track in which the amp 'tude of vibration EDWIN JAY QUINBY. 

